Electric



Jan. 3, 1928. 1,655,178

w. A. BRUNO ELECTRIC COIL AND INDUCTANCE Filed April 24, 1925 2Sheets-Sheet. 1

INVENTOR.

ATTORNEY Jan. 3, 1928.

1,655,178 W. A. BRUNO ELECTRIC COIL AND INDUCTANCE Filed April 24, 19252 Sheets-Sheet 2 INVENTOR.

A TTORNEY Iltl Patented Jan. 3, 1928.

UNITED STATES PATENT oFFice.

WILLIAM ATTILIO BRUNO, OF ASTORIA, NEW YORK.

ELE CTR IC cor; Ann I'NDUCTANCE.

Application filed a rnak, 19 55, ser ai Nb. 25,62 5.

transformers, it being"especial ly desirable" that each inductance orrad o'jfrequ'ency' transformer be uniform as to their 'eleictr cal"characteristics, so as to result iii the'fmaizimum electricalefficiency;and' selectivelyof the circuit.

Its objects are or radio frequency transformer: off'ajtype having thehighest electrical etficijehcy'posst ble, and maximum eliminationof'absorption losses.

I obtain these results by so construction and arranging the inductancesor their supports or mountings, so as to practically eliminate thedefects of inductances commonly used heretofore. Such defects in volvefunctional deficiencies referred to as losses which are due todistributed capacity inherent in most types of inductances.

Current losses are principally caused by the presence of foreignconducting bodies in the vicinity of the electrical field of theinductance itself, and also to dielectric absorption losses due in alarge part to the impropor arrangement of the dielectric in contact withor adjacent to the inductances.

Another object of my invention is to provide an improved method ofassemblin the tickler or feed back coil, thereby providing a. minutecontrol of regeneration in such a circuit.

These and other objects of my invention are set forth in the followingdescription and references hereby made to the accompanying drawings, inwhich similar nu merals of designation refer to similar parts throughoutthe several views.

Fig. 1, is an elevation of a tuning in ductance embodying my invent-ion.

Fig. 2, is a section taken on line 2-2 of Fig. 1.

Fig. 3, is an enlarged section taken on line 33 of Fig. 4, and showsdetails of construction.

Fig. 4, is a. vertical section taken on line 44 of Fig. 5, .but with theprimary and secondary windings omittedfor the sake of clearness.

to provide an indii'ctanice,

'Fig. 5, is 'a top view of the tuning inductance of. which Fig. 4 isa'vertical section taken'on' line 4-4 of Fig. 5, with the ticklerinductance in the position of maximum. coupling. v

A; preferred form of my invention is the inductanceumt'shown in Fig. 1',commonly known 'asa three-circuit tuner having apolygon coil shape andcomprising three inductance eoils a secondary winding 1, primary winding4,1'and the third or tickler winding ',lwhich is shown detail 'in'Figs'.et de-1. The p'olygon coil shape 'i s'forme'dby the end rings 7 7*-which are preferably of hard a e e'i nsul in ma a having holes finnedandlpds'itionedlati 'equal distances to acconirifodat the grass mass,and binding posts or terminals 2, 3, 5, 6, 18, and 19, constructed andassembled as shown in Figs. 1 to 5.

It will be noted by the construction show that I eliminate the use ofsolid cylinders, and in an electric coil or inductance of myconstruction, because of the skeleton coil shape employed and especiallythe use of glass supports which form a part of the coil shape or form,and accommodate the windings forming the coil or coils, I am able toproduce an inductance having comparable electrical characteristics tothat of an air core or self-supporting coil employing no coil form,which type of construction could not be carried out practically in athree-circuit tuning inductance due to the necessity of providing astructure to accommodate the third inductance or tickler winding 10.

For the purpose of controlling the amount of coupling between thesecondary inductance 1, and tickler coil 10, the latter is mounted upona movable shaft on which I have provided an insulated section 11, forthe purpose of keeping dielectric losses to a minimum. This movableinductance or coil 10, consists of a number of turns of copper wireWound in a spiral between insulated sections of shaft or tubing 11,which is slotted along part of its entire length.

An extension 12, is inserted in the insulating shaft 11, and is securedto it by a machine screw or pin 13. In order to prevent accidental movinof the inductance or coil 10, or from revolving of its own accord, Ihave provided a spring 15, on shaft 12, positioned between shoulder ofinsulating member 11, and metal bracket 16. This pro- (hm-s an evenpressure upon said shaft, ihcrcliy preventing accidental moving orrevolving of its own accord of thcinductance mcoil 10. I

Fig. 1, shows a constructional detail in which screw 1:3, is positionedon shaft l2 in rclation to inductance or coil 10, 's0 as to provide astop to prevent a continuous revolving of inductance or coil '10 "ineither directionso as to insure a non-breakingpf coil terminals28aiid29.

In FigI 5, is shown how the inductance or coil lcads'28 a ndi29, arcbroughhto te rilni; nals 18 an' d'l9, through insulating s lia-ft jortube 11, ancl hole in, ring 7, forming the bearing for said i isjulating;sliait or tube [claim andj'desire top'r t'eqt by Letters 4 I sutable riiean s a mounting bracket member,v

Patent 1 1'. An electric coil oi" induetance of,tlie

vertical supports, two en'dr v or insulating material inwliich there ean \VQH number of recesseseyenly snacetl' to" accommodate said 'e rticalsirp p6rts,' asseinbled to" form a, polygo:i a reinfprcenient inter inga section offlielegtric material slotted for part of .its length, aspiral inductance winding, secured to said shaft, said shaft having ametallic extension secured by suitable means and rotatably mounted inend ring pf dielectric material.

' 2. 'An elect ii 'c'coil or inductance of the tyne desoribedcomprisinga set of windings, verfiical'supports, two end rings of dielectric orinsulating material in which there are an even number 10f recessesevenly spaced to accommodate said vert-ical supports, assembled to forma polygon, a reinforcement band of dielectric material disposedintermediate. said StIPIPQll-S, 2lhd a shafthaying a section of ,di-

electiiie material slotted ,forpa rt of its length with a" Iiieta-llicextension secured to it, ,by

afspiralk ritiglgaround "said iiet'al extension, on e fend of springrest ng against I a shoulder; "of saidf insulatijng .section, an

.in ,c 1 r I .4. other, end a ainst said mounting bracket, .50

as to'prbvi'de'a tension iipon's'aid sha bignedat New York, in thecountYork zi'n'd'stajt'e ofiNew Yo'rk, this twentylirst day of April, 1925. ii I "\VILLIIAM"ATTILIO BRUNO.

